Developmental and Comparative Immunology 34 (2010) 1051–1058 Contents lists available at ScienceDirect Developmental and Comparative Immunology journal homepage: www.elsevier.com/locate/dci Correlated expression profile of extracellular matrix-related molecules during the inflammatory response of the teleost fish gilthead seabream Patricia Castillo-Brice ˜ no a , Marta Arizcun-Arizcun b , José Meseguer a , Victoriano Mulero a , Alfonsa García-Ayala a,∗ a Department of Cell Biology and Histology, University of Murcia, Murcia 30100, Spain b Oceanographic Centre of Murcia, Spanish Oceanographic Institute (IEO), Puerto de Mazarrón, 30860 Murcia, Spain article info Article history: Received 12 April 2010 Received in revised form 10 May 2010 Accepted 11 May 2010 Available online 26 May 2010 Keywords: Collagen Extracellular matrix Gene expression correlations Innate immune response Integrins MMPs TIMPs Teleost fish abstract Extracellular matrix (ECM) components, in addition to their structural functions, interact with cell sur- face receptors and intracellular components to modulate the transduction of signals for cell growth, differentiation, migration, proliferation, polarization, apoptosis and inflammation. Our previous findings in the gilthead seabream (Sparus aurata L.), a marine seasonal hermaphrodite teleost fish, have shown that both endocrine and immune stimuli modulate the expression of matrix metalloproteases (MMPs) and tissue inhibitors of MMP (TIMPs). In addition, collagen type I (COL1) induces the expression of some pro-inflammatory cytokines and MMPs in professional phagocytes. Consequently, in this study we use real-time RT-PCR to analyze the gene expression profile of several ECM-related molecules (MMP-2, -9 and -13, TIMP-2a, and -2b, COL1A1, and integrin 1a) in different organs of adult specimens as well as in response to innate immune challenges. Our results showed that liver had the lowest basal levels of them, although they were clearly modulated during injury and infection. In the same way, ECM-related molecules seem to participate in pro-inflammatory processes, being of particular interest COL1 which is synthesized by immune cells and is able to act as autocrine/paracrine stimulus for them. Lastly, we pro- pose that the observed correlations between ECM-related molecules during the inflammatory response should be considered to obtain a more accurate picture of their roles in this process. © 2010 Elsevier Ltd. All rights reserved. 1. Introduction The structural distinctiveness of the properties of tissues and organs is considered to be determined by the extracellular matrix (ECM) and the cells that produce it (Tsang et al., 2009). However, it is only since the discovery of integrins and other ECM receptors two decades ago that ECM has become interesting for researchers, not only as an intercellular and tissue scaffold, but also as a com- plex extracellular environment and key element in a variety of cellular processes covering a wide range of functionality (Huxley- Jones et al., 2009; Rozario and DeSimone, 2009). ECM interacts with diverse cell components and modulates the transduction of signals that regulate cell growth, differentiation, migration, prolif- eration, polarization, death and inflammation (Hynes, 2009; Tsang et al., 2009). Moreover, the correct expression and function of genes controlling ECM–cell and cell–cell interactions provide the Abbreviations: AGs, acidophilic granulocytes; Cq, quantification cycle; EE2, 17- ethynylestradiol; MCs, macrophages; VaDNA, genomic DNA from Vibrio anguillarum. ∗ Corresponding author. Tel.: +34 868884968; fax: +34 868883963. E-mail address: agayala@um.es (A. García-Ayala). necessary environment for normal multicellular tissues behavior (Werb, 1997). Collagen (COL) molecules are a structurally and developmen- tally complex family of proteins, which constitute the major components of the ECM of all metazoans and appear to be rele- vant during their evolution (Heino et al., 2009; Hynes, 2009). They have diverse functions and play a dominant role in maintaining tis- sue structure (Canty and Kadler, 2005; Myllyharju and Kivirikko, 2004). There are almost 30 COL types, among them COL type I accounts for most of the collagen mass in non-cartilaginous tissues, normally as heterotypic fibrils (Canty and Kadler, 2005; Wenstrup et al., 2004; Wess, 2005). Fibroblasts, monocytes, endothelial and other cell types are able to efficiently secrete proCOLs in vivo (Wess, 2005), and these are processed and assembled in the cell surface (Canty and Kadler, 2005). The interactions between cells and COL in the ECM are mediated by a variety of widely described receptors p.e. integrins (ITGs), which upon COL binding, may activate other molecules, such as matrikines, matrix metalloproteases (MMPs), tissue inhibitor of MMP (TIMPs), cytokines and growth factors, which are indispensable for remodeling, inflammatory, immune or wound healing responses (Garnotel et al., 2000; Heino, 2000; Herr and Farndale, 2009; Lee et al., 2007; Leitinger and Hohenester, 0145-305X/$ – see front matter © 2010 Elsevier Ltd. All rights reserved. doi:10.1016/j.dci.2010.05.007